|
Bob,
The motor is 4"
diameter by 7 " long with a 5/8" shaft. When the thing is hooked to a 12V
tractor battery (that's charged) I can't stop the shaft with my hand. It
doesn't have a permanent magnet as far as I can tell - did the simple put a
piece of metal up to it to check.
- - joe
Don't underestimate them old
tape drive motors! If it's as big as a mower deck motor (3-4" in
diameter, 6" or so tall), it's probably got enough oomph for a kiddy
car. In any case, from my experience, it would be better to start out
underpowered......
>>> "John de Rivaz"
<John deRivaz com> 6/25/2002 3:07:56 PM >>>
> I was
checking in my shop and I have a 50 VDC nominal
> motor (that came out
of a 9-track computer tape drive made by DEC)
I would rather doubt it.
The power required to haul a kid about in a toy car
is somewhat more than
move tape. However there is a rule of thumb mentioned
on this list or
possibly a UK one which said that your electric motor can be
1/4 the
horsepower of a gas engine used in a similar application. This is
because
the electric motor is capable of brief overloads, whereas a gas
motor just
stops. Therefore the gas HP has to be the peak load expected. If
you know
the sort of HP a gas engine would be, then divide by 4 and you get
the
electric HP needed. I HP = 746 watts. For a DC motor, the power in watts
=
emf (volts) x current (amps) x efficiency. Efficiency is high, about
90%
(which would be 0.9 in the suggested
calculation).
--
Sincerely, John de
Rivaz: http://www.deRivaz.com :
http://www.AlecHarleyReeves.com
http://www.longevity-report.com :
http://www.autopsychoice.com
:
http://www.cryonics-europe.org
http://www.porthtowan.com
-----
Original Message -----
From: "SolidTech" <SolidTech qwest net>
To:
"'Elec-Trak'" <elec-trak cosmos phy tufts edu>
Sent: 25 June 2002
18:18
Subject: (ET) Kid car idea
> All,
>
Hoping for some thoughts on feasibility (and refinement) of the idea
of
> making a "better than retail" kid car. I know there's the
plastic
electric
> vehicles you can buy at your local toy/department
store. They always seem
a
> bit pricy for the mostly plastic
thing they are. So... I was
contemplating
> a simple
go-cart style vehicle with 1/2/3 batteries, a controller, and an
>
appropriate motor. I was checking in my shop and I have a 50 VDC
nominal
> motor (that came out of a 9-track computer tape drive made by
DEC) and I
see
> there's various controllers on eBay.
Questions: Is that electric motor
> (Ametek brand) even appropriate for
the task? What would be a reasonable
> number/size of
batteries? What would be appropriate for a controller?
>
>
thoughts?
> - - joe
>
> Joseph Rock
> E-15 &
MagnaTrac Hydro 5000 in
Colorado
>
>
|